p53正向凋亡调控因子在吉西他滨诱导胰腺癌细胞凋亡过程中的作用

目的:研究吉西他滨对人胰腺癌AsPC-1细胞体外生长的作用机制.方法:用脂质体转染法将含有p53正向凋亡调控因子(p53 upregulated modulator of apoptosis,PUMA)反义核酸的真核表达载体pcDNA3.1-PUMAAS和空载体pcDNA3.1导入AsPC-1细胞,G418筛选阳性细胞,获得稳定转染的阳性克隆.将转染载体的AsPC-1阳性克隆细胞和未转染载体的AsPC-1细胞分别暴露于浓度为1、5、10和15 μmol/L的吉西他滨溶液中作用72 h.RT-PCR和Western印迹法检测不同组细胞经吉西他滨作用72 h后的PUMA表达水平,MTT检测细胞生长抑制情况, FCM、Hoechst 33258荧光染色和TUNEL法检测细胞凋亡情况.结果:吉西他滨促进AsPC-1细胞凋亡,抑制细胞生长,并有明显的剂量依赖性,在细胞凋亡的同时伴有PUMA表达的上调;当细胞转染PUMA反义核酸抑制PUMA表达后,受吉西他滨作用的细胞中PUMA蛋白表达明显降低,同时伴有细胞凋亡的抑制及细胞增殖明显增加.结论:吉西他滨促进体外AsPC-1细胞凋亡,并抑制细胞生长,其诱导细胞凋亡与上调PUMA表达有关.     

p53 mutations and overexpression in locally advanced breast cancers.

Alterations in the p53 gene were analysed in 39 patients with locally advanced breast cancers (LABCs) (stage III-IV) with inflammatory signs in most cases (UICC stage T4d = 32 patients) by molecular and immunohistochemical (IHC) approaches. All patients were included in the same therapy protocol. Using polymerase chain reaction (PCR) and a single-strand conformational polymorphism migration technique (SSCP), the presence of mutations in exons 2-11, covering the entire coding sequence of the p53 gene, was evaluated. Using the mouse specific anti-human p53 monoclonal antibody (PAb 1801), we also looked for overexpression of the p53 protein in tissue sections. In 16 cases shifted bands were reproducibly identified by PCR-SSCP, and all but one (localised to exon 10) were in exons 5-8, the usual mutational hotspots. Fifteen of these 16 samples were sequenced and 14 of the suspected mutations (36%) were confirmed. Most of them (12) were single nucleotide substitutions, and transitions were more frequent (eight cases) than transversions (four cases). Fourteen of the tumour samples were positively stained with the monoclonal antibody PAb 1801, 11 with nuclear staining only, two with mixed cytoplasmic and nuclear staining and one with cytoplasmic staining only. Staining patterns were very heterogeneous in terms of the percentage of positive cells (10-75%) and their distribution in the tissue section (isolated foci or dispersed cells). In 11 of the 14 mutated cases a positive immunostaining was observed. The presence of a p53 mutation was significantly associated with larger tumour diameter (chi 2 = 7.490, P = 0.0062) and the presence of clinical metastases (stage IV) (chi 2 = 10.113, P = 0.0015). A non-statistically significant trend of association was observed between p53 mutation, negative oestrogen receptors and lower response rate to therapy. Our results in this group of patients and the heterogeneity of the staining of tumour cells in tissue sections suggest that p53 mutations could be a late event in this non-familial form of breast cancer.     

Multimodality treatment of locally advanced breast cancer

From 1976 to 1985, 61 consecutive patients with locally advanced breast cancer were treated with multimodality therapy. Overall 5-year survival was 30% with a median survival of 36 months. 50% of patients relapsed within 13 months. Other factors such as menopausal status, side of illness (right or left breast), responses to systemic or to local treatment, survival and progression-free survival in responders and non-responders have been analyzed.     

局部中晚期非小细胞肺癌的诱导治疗

1　局部中晚期非小细胞肺癌 (ＮＳＣＬＣ)手术前的诱导治疗局部中晚期ＮＳＣＬＣ即使能进行手术切除 ,疗效仍不佳 ,特别是有多组纵隔淋巴结转移的患者 (Ｎ2 ) ,手术治疗后的 5年生存率仅 15 %～ 2 0 %。治疗失败的主要原因是远处转移 ,发生率为 5 0 %～ 80 % ,局部肿瘤复发也是一个重要原因。目前 ,对这部分患者强调进行综合治疗 ,即联合手术、放疗和化疗。主要的综合治疗方法有 :①手术→化放疗 ;②化疗或化放疗→手术 (诱导治疗 )。然而 ,近 10年来的临床实践表明 ,似乎先化疗或先化放疗再手术的综合方法优于先手术后化放疗的疗效。近年来…     

局部晚期乳腺癌的治疗体会

目的:观察85例III期乳腺癌患者治疗的疗效,寻找提高疗效的策略。方法:2003年6月至2005年12月85例III期乳腺癌患者接受了外科手术治疗,根据是否接受新辅助化疗分为手术组(41例)和新辅助化疗组(44例),比较两组的手术性质及治疗结果。结果:新辅助化疗组的无病生存期为59.1个月,明显高于手术组的43.1个月(P<0.05),新辅助化疗组的5年无病生存率为36.16%,手术组为34.14%(P>0.05)。结论:局部晚期乳腺癌患者接受新辅助化疗后手术可提高无病生存时间,值得临床推广。     

局部晚期乳腺癌的治疗进展

新辅助化疗后再手术和（或）放疗已成为治疗局部晚期乳腺癌的治疗模式。本文综述新辅助化疗的依据、疗程方案、影响疗效及预后相关因素及其优缺点，同时介绍了局部晚期乳腺癌诊断，局部治疗及内分泌治疗等方面的进展。     

局部晚期乳腺癌的治疗体会

目的：观察85例III期乳腺癌患者治疗的疗效,寻找提高疗效的策略。方法：2003年6月至2005年12月85例III期乳腺癌患者接受了外科手术治疗,根据是否接受新辅助化疗分为手术组（41例）和新辅助化疗组（44例）,比较两组的手术性质及治疗结果。结果：新辅助化疗组的无病生存期为59.1个月,明显高于手术组的43.1个月（P〈0.05）,新辅助化疗组的5年无病生存率为36.16%,手术组为34.14%（P〉0.05）。结论：局部晚期乳腺癌患者接受新辅助化疗后手术可提高无病生存时间,值得临床推广。     

Treatment of locally advanced breast cancer.

It is possible to convert most patients with stage III breast cancer to the state of "no evidence of disease." The challenges now are to increase the cure rate by eradicating local and distant micrometastatic disease, and to minimize the mutilation of locoregional treatment.     

Role of p53 up-regulated modulator of apoptosis and phosphorylated Akt in melanoma cell growth, apoptosis, and patient survival

Malignant melanoma is an aggressive and chemoresistant form of skin cancer characterized by rapid metastasis and poor patient prognosis. The development of innovative therapies with improved efficacy is critical to treatment of this disease. Here, we show that aberrant expression of two proteins, p53 up-regulated modulator of apoptosis (PUMA) and phosphorylated Akt (p-Akt), is associated with poor patient survival. Using tissue microarray analysis, we found that patients exhibiting both weak PUMA expression and strong p-Akt expression in their melanoma tumor tissue had significantly worse 5-year survival than patients with either weak PUMA or strong p-Akt expression alone (P < 0.001). Strikingly, no patients exhibiting strong PUMA expression and weak p-Akt expression in primary tumor tissue died within 5 years of diagnosis. We propose a two-pronged therapeutic strategy of (a) boosting PUMA expression and (b) inhibiting Akt phosphorylation in melanoma tumor tissue. Here, we report that a recombinant adenovirus containing human PUMA cDNA (ad-PUMA) efficiently inhibits human melanoma cell survival in vitro, rapidly induces apoptosis, and dramatically suppresses human melanoma tumor growth in a severe combined immunodeficient mouse xenograft model. In melanoma cells strongly expressing p-Akt, we show that Akt/protein kinase B signaling inhibitor-2 (API-2; a small-molecule Akt inhibitor) reduces cell survival in a dose- and time-dependent manner and enhances ad-PUMA-mediated growth inhibition of melanoma cells. Finally, we show that, by combining ad-PUMA and API-2 treatments, human melanoma tumor growth can be inhibited by >80% in vivo compared with controls. Our results suggest that a strategy to correct dysregulated PUMA and p-Akt expression in malignant melanoma may be an effective therapeutic option.     

MRI and conservative treatment of locally advanced breast cancer

AIMS: The objectives of this study were to compare the efficacy of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in assessing the response of primary breast carcinoma to neoadjuvant chemotherapy compared to conventional imaging modalities, and to see how surgical outcome was influenced as a result of these findings. METHODS: Thirty-four patients with locally advanced primary breast cancer underwent conventional imaging and DCE-MRI following six cycles of neoadjuvant chemotherapy prior to surgery. Changes in surgical management based on the post-chemotherapy DCE-MRI findings were recorded. RESULTS: Prior to neoadjuvant chemotherapy, 22 of the 34 patients were assessed as requiring mastectomy and the remaining 12 were considered inoperable. Following chemotherapy two patients were still considered inoperable. In 11 of the 34 patients, the final decision to proceed to either mastectomy or non-surgical management was based primarily on pre-treatment disease status or patient choice. DCE-MRI findings, therefore, contributed to the operative decision in 21 of 34 patients. Two of these 21 patients were spared surgery as DCE-MRI demonstrated complete response to chemotherapy and one declined surgery. The remaining 18 were able to undergo wide local excision, with only two patients subsequently requiring mastectomy for involved margins. CONCLUSIONS: DCE-MRI is able to accurately predict those patients suitable for breast conserving surgery following neoadjuvant chemotherapy and should be the imaging modality of choice in assessing the response of patients with primary breast carcinoma to neoadjuvant chemotherapy.     

Intra-arterial infusion chemotherapy as preoperative treatment of locally advanced breast cancer.

Intra-arterial infusion chemotherapy was made through the internal mammary artery and subclavian artery in 12 cases of locally advanced breast cancer. Continuous infusion of 5-fluorouracil and intermittent injections of Mitomycin C were jointly made for 1 to 4 weeks in each artery. Marked response in not only the primary tumor but also lymph node metastasis was clinically observed, permitting extended radical mastectomy successfully in all cases. Remarkable regressive changes were histologically observed in cancer foci, especially in small ones, of resected specimens including axillary, parasternal, and supraclavicular lymph nodes. All cases except 1 have been healthy without any recurrence for 22 to 78 months after treatment. Intra-arterial infusion chemotherapy will this method is a useful preliminary procedure for surgical treatment of locally advanced breast cancer.     

长春瑞滨联合顺铂治疗晚期乳腺癌的临床观察

目的探讨长春瑞滨联合顺铂治疗经紫杉醇＋蒽环类联合化疗失败的局部晚期乳腺癌和复发转移乳腺癌的疗效及安全性。方法10例采用紫杉醇＋蒽环类化疗耐药的局部晚期乳腺癌和31例手术后紫杉醇＋蒽环类辅助治疗的转移性乳腺癌患者,应用长春瑞滨（25mg／m^2,第1,8天,静脉滴注）、顺铂（30mg／m^2,第1—3天,静脉滴注）化疗,对其疗效及不良反应进行分析。结果全组患者完全缓解6例（14．6％）,部分缓解17例（41．5％）。不良反应以骨髓抑制、消化道反应常见。结论长春瑞滨联合顺铂方案对蒽环类和（或）紫杉醇耐药的乳腺癌疗效较好,值得临床进一步研究。     

Fast neutrons in the treatment of locally advanced breast cancer

The clinical investigation of fast neutrons at Hammersmith Hospital included 17 patients who between them had 20 T4 breast cancers. The majority of these tumours were ulcerated and all were painful. Ten had recurred after multiple other therapies. Complete local regression was achieved in all but one (95%) and no tumour recurred. Symptoms were relieved in all cases. Median survival was 26 months. Three patients developed small areas of skin necrosis following trauma of previous radiation. All the neutron treated breasts became fibrosed, but this was painless. Neutron treatment needed only 12 attendances over 28 days, in contrast to the best results from photon therapy which required 6-7 weeks followed by implant of radioactive wire and/or surgical excision. One patient who had bilateral tumours received neutrons to the left breast and X-ray therapy (photons) to the right. The photon treated tumour did not completely regress and recurred. The neutron treated one completely regressed and did not recur. Neutrons were also more effective than tamoxifen which causes complete regression in only about 30% of cases. It is suggested that neutron therapy is indicated for locally advanced tumours which do not respond to hormones. Since metastases were a common cause of death, there remains a need for an effective adjuvant treatment, acceptable to elderly patients.     

p53-independent death and p53-induced protection against apoptosis in fibroblasts treated with chemotherapeutic drugs.

Many recent studies have implicated p53 in the cellular response to injury and induction of cell death by apoptosis. In a rat embryonal fibroblast cell line transformed with c-Ha-ras and a mutant temperature-sensitive p53 (val135), cells were G1 arrested at the permissive temperature of 32 degrees C when overexpressed p53 was in wild-type conformation. In this state cells were resistant to apoptosis induced by etoposide (at up to 50 microM) or bleomycin (15 microU ml-1). Cells at 37 degrees C with overexpressed p53 in mutant conformation were freed from this growth arrest, continued proliferating and showed dose-dependent increases in apoptosis. This death is independent of wild-type p53 function. Control cells containing a non-temperature-sensitive mutant p53 (phe132) were sensitive to both etoposide and bleomycin after 24 h at 32 degrees C and 37 degrees C, indicating that the results are not simply due to temperature effects on pharmacokinetics or DNA damage. Our data show that induction of a stable p53-mediated growth arrest renders these cells much less likely to undergo apoptosis in response to certain anti-cancer drugs, and we conclude that the regulatory role of p53 in apoptosis is influenced by the particular cellular context in which this gene is expressed.     

p53 mutations in breast cancer.

We have identified and analyzed 41 mutations in p53 in sporadic breast tumors from 136 unselected breast cancer patients and estimate that approximately 40% of such tumors contain p53 mutations. The frequency of G-T transversions and the incidence of guanosine mutations in the nontranscribed strand of the p53 gene were found to be higher than expected, and we suggest, therefore, that exogenous carcinogens have an etiological role in sporadic breast cancers. Mutations were recorded in 44 codons of the p53 gene, with no obvious mutational hot-spots, although mutations at codons 175, 194, 273, and 280 accounted for 25% of the changes. One germ-line mutation was found in 136 patients and so we conclude that constitutional mutation of p53 may be an uncommon etiological factor in breast cancer.